Typically, a mining engineer employs a site specific convention and historical practice to determine the locations for crown pillars/sub-levels and pillars/stopes. Stoping is, generally, a process of extracting ore from an underground mine. This leaves behind an open space, which is known as a “stope.” A pillar is untouched mining material. A crown pillar is a pillar of ore left for safety and stability reasons between the base of the open-pit and the first level of underground mining and between stopes at different levels in the underground mine to ensure adequate support/safety. The site specific convention often employs fixed height/width strategies for sub-levels/crown pillars and stopes/pillars. An example of a fixed height/width strategy is setting all sub-levels to be 30 m high and all crown pillars to be 5 m high.